Data collected in past and ongoing research studies have the potential to increase knowledge of etiology and trajectories of HIV-associated neurobehavioral and psychosocial consequences on activities of daily functioning and to serve as a guide in the development of novel, high quality, effective interventions for the prevention and treatment of these consequences. However, few efforts have been made to combine data across studies. Although such efforts would significantly increase the value of the collected data to address HIV-related questions, several technical and non-technical barriers exist. We have addressed such barriers in the AHRQ-funded Washington Heights Inwood Informatics Infrastructure for Comparative Effectiveness Research (WICER) and its successor (WICER 4 U) and we build upon these experiences to create the Innovative Informatics Infrastructure to Support Data Integration Exploration and Analysis for Longitudinal Studies (I3DEAL) for HIV Research. Although data sharing among heterogeneous healthcare systems in a manner in which all data are understood by both the sending and receiving systems (i.e., semantic interoperability) has not been achieved, significant progress has been made and there is agreement that syntactic approaches are insufficient for this purpose. Semantic approaches are particularly relevant to I3DEAL for HIV Research for multiple reasons including the fact that we will be integrating not only heterogeneous HIV research data sets, but also de-identified clinical data from the WICER Research Data Warehouse (RDW) and the NewYork-Presbyterian Columbia University Medical Center (NYP-CUMC) RDW, to create the I3DEAL for HIV Research RDW. Because of extensive expertise in informatics and HIV including its neurobehavioral and psychosocial consequences, our research team is uniquely qualified to achieve the specific aims of I3DEAL for HIV Research which are to: 1. Implement semantic approaches to formally represent and integrate the items from a diverse collection of existing HIV longitudinal data sets to create the I3DEAL for HIV Research RDW. 2. Apply and refine innovative algorithmic methods to discover HIV negative individuals from the WICER RDW and NYP-CUMC RDW to create a common database of neurobehavioral and psychosocial norms for integration into the I3DEAL for HIV Research RDW. 3. Refine Research Data Explorer (RedX) to meet the needs of HIV investigators. The primary products of I3DEAL for HIV Research will be the I3DEAL for HIV Research RDW including the common database of neurobehavioral and psychosocial norms, two informatics tools refined for HIV research: the Statistical CorRection of Uncharacterized Bias (SCRUB) algorithm and RedX query tool, and data governance policies and procedures.